JP3374195B2 - Chain stitch sewing machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chain stitch sewing machine that performs chain stitch sewing on a cloth by selectively using a plurality of threads. 2. Description of the Related Art A needle plate, a sewing needle provided above and below the needle plate so as to be movable up and down, and a plurality of loopers disposed below the needle plate so as to be interchangeable for selective use. A chain stitch sewing machine having a structure including a thread cutting device disposed below the needle plate for cutting a thread between the needle plate and the looper is known (for example, Japanese Patent Publication No. 3-11239). Reference). In such a sewing machine, when sewing with one thread is completed, the thread is cut there and the looper is replaced, so that sewing with the next thread can be performed subsequently. [0003] However, when sewing with the next thread is started, the previous thread remains in the needle hole. If the thin thread of the first thread is lightly twisted, the fluff of the former thread or some of the thin thread in the latter thread is caught on the needle, which is raised by the rise of the needle, and the next thread There was a problem that it appeared in a mixed state in the seam. In order to solve the problem, after sewing with one thread and cutting the thread, the needle is largely raised, and the cut end of the thread is pulled up through the needle hole through the cloth to the upper surface side of the cloth. Was tried. However, if you do so, after finishing all sewing on the cloth and removing the cloth from the sewing machine,
When trying to prevent the end of the thread used for each sewing from being removed on the side that was the lower surface of the cloth, each thread end on the side that was the upper surface of the cloth was the lower surface through the cloth. There is a problem that a cumbersome operation of putting it to the side is required. The present invention has been made in order to solve the above-mentioned problems (technical problems) of the prior art. In the case where sewing with one thread is completed and then sewing with the next thread is started, If the previous thread can be prevented from being erroneously pulled up and the next thread can be sewn properly, and if the thread end is to be removed after finishing all sewing on the cloth, the sewing end state It is an object of the present invention to provide a chain stitch sewing machine capable of performing the work without any modification. A chain stitch sewing machine according to the present invention comprises a needle plate provided with a needle hole, a sewing needle provided vertically movable above the needle plate, and a sewing plate provided below the needle plate. A plurality of loopers arranged interchangeably for selective use, and a thread cutter disposed below the needle plate for cutting a yarn between the needle hole and the looper in the needle plate. In the chain stitch sewing machine provided with a device, after cutting the thread by the thread cutting device below the needle plate, the thread in the needle hole and connected to the cloth on the needle plate is removed. The wiping member for extracting from the needle hole to the lower surface side of the cloth is located between the concave position for accommodating the wiping member formed on the upper surface of the needle plate and the position passing through the position where the needle hole overlaps the needle hole in the needle plate. The reciprocating motion along the upper surface of the throat plate is provided at The thread on the side of the cloth on the needle plate is drawn out from the needle hole to the lower side of the cloth, and the wiping member is always used for accommodating the wiping member formed on the upper surface of the needle plate. In the recess. When the sewing with one thread is completed, the thread is cut by a thread cutting device. After the cutting, the yarn on the side connected to the cloth is removed by a wiping member that moves laterally along the upper surface of the needle plate. Therefore, the thread is pulled out from the needle hole and is in a state along the lower surface of the cloth. Then, the looper is replaced and sewing with the next thread is started. An embodiment of the present invention will be described below with reference to the drawings. Reference numerals 1 to 15 denote members of a well-known chain stitch sewing machine. Reference numeral 1 denotes a bed plate which is attached to a base frame of the sewing machine. A needle plate 2 is attached to the bed plate 1 with a set screw 3. Reference numeral 4 denotes a needle hole, and reference numeral 5 denotes a threading hole. 4a is a needle hole having a different diameter, and 5a is a threading hole provided corresponding to the needle hole. These needle holes are rotated by 180 degrees when the needle plate 2 is viewed in a plane, so that the needle hole 4 and the threading hole 5 are formed. Is used in exchange for them at the location where they were. Reference numeral 6 denotes a lid for closing a maintenance hole formed in the bed plate, which is attached with a fixing screw 7. Reference numeral 8 denotes a needle for sewing, which is movable up and down, and has a hook 9. Numeral 11 denotes a looper base, which is provided so as to be freely movable in a lateral direction with respect to a base frame of the sewing machine. Reference numerals 12, 12,... Denote a plurality of loopers mounted on the looper base 11, which are exchangeably arranged immediately below the needle holes 4 by lateral movement of the looper base 11. Each looper has a different type (eg, color,
(Thickness, properties, etc.). 13 is looper stand 11
Is a driving rod for driving the. Reference numeral 15 denotes a yarn cutting device provided below the needle plate 2, and a movable member for drawing in the yarn advances and retreats to a position between the needle hole 4 and the looper 12 as shown by arrows 15a and 15b to cut the yarn. It has become. Next, reference numeral 17 denotes a recess for accommodating a wiping member formed on the upper surface of the bed plate 1, and reference numeral 18 denotes a bearing hole formed in the bed plate 1. Reference numerals 19 and 20 are guide pieces attached to the bed plate 1, and their upper surfaces are arcuate guide surfaces 19a and 20a as shown in FIGS. 7 and 6, respectively.
Reference numeral 21 denotes a wiping member, which is capable of laterally moving along the upper surface of the needle plate 2, for example, in the present example, is configured to make an arc movement along the upper surface of the needle plate 2 around a shaft body 22 provided at the base. . A parallel movement may be made along the upper surface of the needle plate 2. The shaft body 22 is supported by the bearing hole 18 so as to be able to rotate and move back and forth in the axial direction. Reference numeral 23 shown in FIG. 4 denotes an urging member for urging the wiping member 21 toward the bed plate 1, for example, a spring for urging downward in this example, and a spring receiving portion 24 constituted by a part of the bed plate 1. And spring seat 25 attached to shaft 22
Interposed between 26 is a passive lever fixed to the shaft 22. Reference numeral 27 denotes a fitting hole formed at a position corresponding to the guide piece 20. Next, the reference numeral 30 shown in FIG. 31 is a motor in the mechanism, 32 is a cam, and has a cam groove 32a around it. Reference numeral 33 denotes a drive lever, which is rotatably supported at an intermediate portion 33c, and has a follower provided at one end.
33a is engaged with the cam groove 32a, and an engagement piece 33b provided at the other end is provided.
Is engaged with an engagement hole 26a provided in the passive lever 26.
In the drive mechanism 30, the cam member 32 makes one rotation of the cam 32 by the motor 31 so that the drive member 33 and the
Makes one reciprocation in the direction of the arrow. In the above-mentioned construction, the looper 12 and the needle 8 operate in a known manner, and the sewing to the cloth 35 is performed by the thread 36 supplied through the looper 12, as shown in FIG. Will be That is, the needle 8 descends from the top dead center through the needle hole 4 to the bottom dead center, and then the looper 12 rotates and the thread hooks on the hook 9, and then the needle 8 moves toward the top dead center. Ascending, the yarn is pulled up. In the course of this ascent, the upholstery frame holding the cloth 35 is
The cloth 35 is laterally moved by the dimension of the eye, and the cloth 35 is laterally moved by the same dimension. Such an operation is repeatedly performed. Next, after the sewing with one thread is completed, the sewing operation with the next thread is performed as follows. At the end point of sewing with one thread, the needle 8 moves to the top dead center as shown in FIG. 7A without laterally moving the embroidery frame. Thereafter, the movable portion of the yarn cutting device 15 reciprocates as shown by arrows 15a and 15b, and cuts the yarn 36 'located between the needle hole 4 and the looper 12. Next, the payment member
21 is reciprocated by the drive mechanism 30 as described above. In this case, in the course of the forward movement, first, the guide surfaces 19a and 20a of the guide pieces 19 and 20 are changed from the state of FIGS. 6A and 7A.
6B, the wiping member 21 is lifted up as shown in FIGS. 6B and 7B. Subsequently, the payment member 21 is shown in FIG.
As shown by an arrow 37 in (C) of FIG. 7B, it moves laterally along the upper surface of the needle plate 2 through a position overlapping with the needle hole 4. In this way, by passing through the position where the wiping member 21 overlaps with the needle hole 4 and stopping at a predetermined arbitrary position as shown in the figure, the cutting thread 36 is connected to the cloth 35 in the cut thread 36. The thread on the side of the needle, that is, the thread remaining in the needle hole 4 as shown in FIG.
36a is pulled out from the needle hole 4 as shown in FIG.
35 will be along the lower surface. The post-payment member 21 then moves back and returns to the position in the recess 17. Then, the lateral movement of the cloth 35 is performed by the lateral movement of the embroidery frame. In parallel with the above, that is, after the yarn is cut by the yarn cutting device 15 and before or after the horizontal movement of the cloth, the horizontal movement of the looper table 11 causes the looper table 11 to move immediately below the needle hole 4. Next, a looper 12 is provided which is loaded with a thread to be used for sewing. Thereafter, the sewing with the next thread is performed by the same operation as described above, that is, the vertical movement of the needle 8 and the operation of the looper 12. Even if the thread 36a is returned to the side of the needle hole 4 at the time of the returning movement of the wiping member 21, the thread 36a does not enter the inside of the needle hole 4, so that the sewing with the next thread is performed. The possibility that the thread 36a is accidentally caught on the needle 8 is small. When all sewing on the cloth is completed, the cloth 35
Is removed from the embroidery frame, and a well-known process for preventing the thread ends from unraveling on the back surface (the lower surface) of the cloth, for example, in the area where the sewing (embroidery) is performed on the cloth Processing such as applying a small amount of glue to the back surface, sewing the cloth 35 on another cloth, and wrapping a thread end on the back surface of the cloth is performed. As described above, in the present invention, the cloth 35
When performing sewing, not only has the feature that, by selecting a plurality of loopers 12, it is possible to select and use a plurality of types of threads for sewing, but also to finish sewing with one thread, cut the thread, and then continue. When sewing is to be performed using another thread, there is a feature that the thread remaining in the needle hole 4 can be removed from the inside of the needle hole 4 by the wiping member 21. This means that even if the previous thread is a thread with a lot of fluff or a thread in which several thin threads are lightly twisted, the thread before the next thread must be pulled up at the start of sewing with the next thread. This has the effect of reliably preventing the sewage and appropriately performing sewing with the next thread. Moreover, even if the thread is removed from the needle hole 4 as described above, the removed thread 36a moves along the upper surface of the needle plate 2, so that the removed thread 36a is placed on the lower surface of the cloth 35. There is a feature that can be pulled out. This means that, after finishing all the sewing on the cloth, when processing the thread end on the side which was the lower surface of the cloth 35, the sewing end state is not changed without any modification (as in the above-mentioned prior art, There is the convenience that the processing operation can be performed (without the necessity of passing the thread on the lower side through the lower side). Further, in the present invention, the wiping member 21 is
The reciprocating movement along the upper surface of the needle plate 1 is performed between the position of the recess 17 for accommodating the wiping member formed on the upper surface of the needle plate 1 and the position passing through the position overlapping with the needle hole 4 in the needle plate. The thread 36a on the side connected to the cloth 35 on the needle plate is removably moved by the reciprocating movement of the wiping member 21 so that the needle hole 4
From the needle 35 to the lower surface of the cloth 35 from the needle hole 4 in an extremely rapid manner. There are operational effects that can be achieved. Further, as described above, the upper surface of the needle plate 1 is located between the position of the recess 17 for accommodating the wiping member formed on the upper surface of the needle plate 1 and the position passing through the position overlapping with the needle hole 4 in the needle plate 1. Even if the sweeping member 21 is freely provided with a reciprocating motion along the swaging member 21, the sweeping member 21 is normally set in a recess for accommodating the sweeping member formed on the upper surface of the needle plate 1. At all times,
The upper surface of the wiping member 21 can be used as a surface for receiving the cloth similarly to the upper surface of the needle plate 1, and there is an effect that the cloth handling is not hindered.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic longitudinal sectional view of a chain stitch sewing machine. FIG. 2 is a plan view showing a state near a needle plate on an upper surface of a bed plate in the chain stitch sewing machine. FIG. 3 is an exploded perspective view showing a relationship between a wiping member, a bed plate, and a needle plate. FIG. 4 is an enlarged sectional view taken along line IV-IV in FIG. 2; FIG. 5 is a mechanism diagram showing a driving mechanism of a wiping member. 6A is an enlarged sectional view taken along line VI-VI in FIG.
(B) is sectional drawing which shows the state at the time of the operation | movement start of a wiping member. FIGS. 7A, 7B, and 7C are cross-sectional views for explaining the operation of the wiping member. [Description of Signs] 2 Needle plate 4 Needle hole 8 Needle 12 Looper 15 Thread cutting device 21 Paying member

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-5263 (JP, A) JP-A-59-211670 (JP, A) JP-A-5-23957 (JP, A) 2092 (JP, U) JP 3-11239 (JP, B2) JP 1-53385 (JP, B2) JP 61-27075 (JP, B2) Patent 2866504 (JP, B2) −504594 (JP, A) (58) Fields surveyed (Int. Cl. ⁷ , DB name) D05B 1/00-97/12

Claims (1)

(57) [Claims 1] A needle plate having a needle hole, a sewing needle provided vertically movable above the needle plate, and a needle below the needle plate for selective use. A plurality of loopers that are exchangeably disposed on the needle plate, and a thread cutting device disposed below the needle plate to cut a thread between the needle hole and the looper in the needle plate. In the sewing machine, after the yarn is cut by the yarn cutting device below the needle plate, the yarn that is in the needle hole and that is continuous with the cloth on the needle plate is moved from the needle hole to the cloth. The wiping member for extracting to the lower surface side is provided on the upper surface of the needle plate between a concave position for accommodating the wiping member formed on the upper surface of the needle plate and a position passing through a position overlapping with the needle hole in the needle plate. Reciprocating along the needle plate and reciprocating the wiping member to connect the cloth on the needle plate The thread is pulled out from the needle hole to the lower surface side of the cloth, and the wiping member is normally set in a recess for accommodating the wiping member formed on the upper surface of the needle plate. Chain stitch sewing machine.